Question

A neonate born to a 41-year-old woman in her 39th week of gestation has a flattened face and epicanthal folds. The child's echocardiography reveals an endocardial cushion defect. Which of the following most likely occurred prior to conception?

Option 1: Meiotic non-disjunction
Option 2: Robertsonian translocation
Option 3: Expansion of trinucleotide repeats
Option 4: Formation of fragile site
Option 5: Inactivation of one chromosome
Option 6: Deletion of chromosomal part

Answer 1

Meiotic non-disjunction is the most likely event that occurred prior to conception.

Step-by-step explanation:

The most likely event that occurred prior to conception in this case is Meiotic non-disjunction. Meiotic non-disjunction is an error in the separation of chromosomes during meiosis, resulting in an abnormal number of chromosomes in the resulting gametes. This can lead to genetic disorders and birth defects.